Transmission



Feb. 6, 1945. w. l.. PoLLARD TRANSMISSION Filed April 17, 1942 2 Sheets-Sheet 2 Ililwlrmlxml un. Nn .l..

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Application April 17, 1942, Serial No. 439,365

7 Claims. (Cl. 74189.5)

My invention relates to hydraulic transmissions.

One of the objects of my invention is to provide an improved hydro-planetary transmission which will have a long torque ratio range.

A further object is to provide an improved hydro-planetary transmission which will have a high starting torque.

A further object of my invention is to provide an improved hydro-planetary transmission which will have a long torque ratio range and a continuous power flow.

A further object is to provide an improved hydro-planetary transmission which will have a long torque ratio range and continuous power flow, and in which the use of control clutches or brakes is avoided.

Further objects and advantages of the invention will be apparent from the description and claims.

In the drawings in which several forms of my invention are shown,

Figure 1 is an axial sectional view showing one form of hydro-planetary transmissiom'.

Figs. 2, 3, and 4 show, respectively, axial sections of other forms;

Fig. 5 is a. view showing characteristic curves obtainable from some of these transmissions;

Fig. 6 is an axial sectional view of another form of hydro-planetary transmission; and

Figs. 7, 8, 9, and 10 show, respectively, axial sections of other forms.

Referring to Fig. 1 in detail, the construction shown comprises an input shaft I, an output shaft 2, an intermediate shaft 3, a torque converter 4, a torque converter 5 in tandem power flow relation to the converter 4, a planetary gear 6 for effecting premature transformation to coupling action of the converters 4 and 5, and a planetary gear 1 for combining the divided power flow from the pump 8 to the output shaft 2. The front converter comprises the pump rotor 9 keyed to the shaft I, the turbine rotor I keyed to the shaft 3, and the one-Way rotatable turbo-stator II. The torque converter comprises a pump 8, the turbine rotor I2, and the stator-rotor I3. The planetary 6 comprises the sun gear I4 connected with the stator I3, the ring gear I 4a, the planet gearing I5 meshing with the sun gear and ring gear, and the gear carrier I6 on which the planet gearing I5 is mounted. The gear carrier I8 is fast to the sleeve I'I to which the turbine rotor I2 is secured. A one-way anchor I8 is provided to prevent reverse rotation of the stator I3.

'Ihe planetary gear I comprises the sun gear Is keyed to the intermediate shaft a, to winnii the pump rotor 8 is secured, the ring gear 2|, planet gearing 2I meshing with the sun gear and ring gear, and a gear carrier 22 fast to the output shaft 2. A one-way anchor 23 is provided to prevent reverse rotation of the ring gear.

In operation, assuming that the car is standing still, in the rst stage the pump rotor 9 will pass an increased torque to the turbine I0 which, for example, might be 4:1, and this will be transmitted to the sun gear I9. The torque will again be multiplied by, for example, three in the planetary unit I9, 20, 2|, and 22, since the ring gear 20 is held against reverse rotation. This will give an over-all torque ratio of 12:1. During the slow speed of the pump rotor I 0, very little drag will be exerted on the pump rotor 8 but as the speed of the pump rotor 8 increases, a point will be reached when the turbine I2 will begin to rotate, after which there will be a divided power flow from the turbine rotor I8. One branch will pass through the torque converter 5, sleeve II, planetary gearing 6, ring gear 20, and planet gearing 2| to the gear carrier 22. The other branch will be from the turbine rotor I0, through the intermediate shaft 3 to the sun gear I9. The torque and efilciency curve for this construction will be approximately as shown in Fig. 5. The front planetary gearing 8 may be omitted if desired, in which case the shaft I1 would be connected directly to the ring gear 28. The purpose of the front planetary 6 is to provide a premature transformation from converter action to coupler action of the converters 4 and 5. A transmission using some such power circuit might be advantageous in tanks where high initial torque is needed and where it might be desirable to get rid of all clutches and brakes.

The construction shown in Fig. 2 is in general similar to that shown in Fig. 1, comprising the input shaft I, rthe output shaft 2, the intermediate shaft 3, the converters 4 and 5, and the planetary 1. One-way anchors 24, 25, and 28 are provided to prevent reverse rotation of the stators II and I3 and of the ring gear 28. In both of these forms it will be noted that the second stage pump 8 and sun gear I9 are connected to rotate as a unit with the primary stage turbine I 0 and that the ring gear 20 is connected so as to be driven by the second stage turbine I2 and is held against reverse rotation by a one-way anchor. 'I'he operation of this form is broadly similar to that of Fig. 1, it being noted that in both forms the turbine of the iirst converter drives the pump of the second converter and that the hydraulic torque converter 5. This construction comprises the input shaft I, the output shaft 2, the intermediate shaft 3, the torque converter 4, the hydraulicv coupler 21 and the planetary gearing 28. The coupler pump 29 and the ring gear 30 rotate as a unit with the turbine rotor I0. The coupler turbine 3| rotates as a. unit with the sun gear 32. The gear carrier 33 rotates with the output shaft 2. A one-way anchor 34 is provided to prevent reverse rotation of the sun gear 32.

In this form, assuming that the car is standing still, in the rst stage of movement power fiow will be through the converter 4, intermediate shaft 3, ring gear 38 and gear carrier 33 to the output shaft 2, the sun gear 33 being held against reverse rotation. This will give two stages of torque multiplication-one in the converter 4 and the other in the planetary 28. When the drag on the pump 29 becomes great enough with the increasing speed to start the turbine rotor 3| to rotating, lpower iiow will be divided between the turbine rotor I and output shaft 2, one -branch going through the intermediate shaft 3 and ring gear 30 and the other branch going through the coupler 21 and sun gear 32. This for'm might be useful for truck drives, as it would have two torque multiplications in series in the low gear range.

The construction shown in Fig. 4 is in general like that shown in Fig. 3, except that here two hydraulic couplers are arranged in tandem. The construction shown comprises the input shaft I, the output shaft 2, the intermediate shaft 3, a duplex tandem hydraulic coupler 35, and a planetary gearing 1. The duplex tandem coupler comprises a pump rotor 36 fast to the input shaft I, a turbine rotor 31 keyed to the intermediate shaft 3, a second pump rotor 38 which may be integral with the turbine rotor 31, and a second turbine rotor 39 keyed to the hollow shaft 4D on which the ring gear is mounted. A one-way anchor 4I is provided to prevent reverse rotation of the ring gear 20. In this form, when the car is standing still during the first stage of action, power flow will be mainly from the turbine rotor 31 to the sun gear I9 as there is very little drag on the pump rotor 38 during the slow movement stage of the turbine 31. As the turbine 31 picks up in speed, the drag on the pump 38 will increase until it is of sufficient amount to start the turbine rotor 39 to moving, after which there will be divided power flow, one branch going to the ring gear 28 and the other branch going to the sun gear I8.

The construction shown in Fig. 6 comprises a twin disc clutch construction 42, a shaft 43 rotatable with one of the clutch discs 44 for direct drive, a tubular shaft 45 rotatable with the other clutch disc 46 for hydro-planetary drive, a first hydraulic torque converter 41, the pump rotor 48 of which is secured tothe tubular shaft 4-5 on which the clutch disc 46 is mounted, a second hydraulic torque converter 49, the pump rotor 50 of which is keyed to the tubular shaft 5| on which the first turbine rotor 52 is mounted, a planetary gearing 53, the ring gear 54 of which is connected to rotate with the turbine rotor 55 of the second torque converter, and the sun gear 58 of which is connected to rotate with the turbine rotor 52 of the rst torque converter, a oneway driving clutch member 51 secured to rotate with the gear carrier 58 of the planetary gearing, and a one-way driven clutch member '59 secured to rotate with the direct drive shaft 43. Suitable antifriction bearings 60 are provided for the various rotating parts.

The twin disc clutch construction comprises a driving head 6I whih may be connected with the motor, the twoalternatively connectible discs 44 and 46 to which reference has lbeen made, and mechanism 62 for selectively and alternatively connecting one or the other of the clutch discs 44 or 46 to rotate with the driving head 6I.

The rst hydraulic torque converter 41 comprises the nonrotatable casing 63 to which the guide or stator blades 64 are secured, the pump rotor 48, and the turbine rotor 52 to which the turbine blades 65 are secured.

The second hydraulic torque converter comprises the pump rotor 50 and turbine rotor 55, to which reference has previously been made, and the nonrotatable casing 63 carrying the guide or reactance blades 61. The ring gear 54 is held against rotation in a direction reverse to that of the pump 50 Iby means of the one-way anchor 68.

In this form, assuming that the car is initially stationary, the first stage of power flow will be from the converter turbine 52 to the sun gear 56, the ring gear 54 being held against reverse rotation by the one-way anchor 6B. This will give a torque multiplication of 5:1 in the converter and perhaps 3:1 in the planetary, giving an over-al1 torque ratio of 1:15. As the speed of the turbine 52 and pump 50 increases, a point will be reached when the drag on .the puinp5,l) ,will be sufficient to start the ring gear 54 tov mov1ng,`"'

after which there will be a divided power ow as in the forms previously described. When a sufficient speed has been obtained, the clutch 42 may beoperated to eliminate the fluid drive action` giving a direct drive through the shaft 43.

The construction shown somewhat diagramn matically in Fig. '7 comprises a drive shaft I, a driven shaft 2, an intermediate shaft 3, a first hydraulic torque converter 4, a rst planetary gear ing 6 for effecting advanced transformation from converter action to coupler action of the converter 4, a second torque converter 5, a second planetary 6a for effecting advanced transformation of the second torque converter 5, and a third planetary gearing 1, the ring gear 20 of which is connected to the turbine rotor of the second torque converter 5 and held against reverse rotation by the one-Way anchor 26 and the sun gear I9 of Winch is keyedv to the intermediate shaft 3 and the gear carrier of which is secured to the driven shaft 2. The gear carrier of the first planetary gearing 6 is keyed to the drive shaft I, and the gear carrier of the second planetary gearing 6a is keyed to the intermediate shaft 3. The operation of this form will be substantially like that of Figs. 1 and 2.

The construction shown in Fig. 8 comprises a drive shaft I, a driven shaft 2, an intermediate shaft 3, a first planetary gearing 6 for effecting a divided power flow through and around the rst hydraulic torque converter 4, a second planetary gearing 8a for effecting an advanced transformation from converter action to couple-r action of the second torque converter 3, and a third planetary gearing 1, the ring gear 20 of which is rotatable with the tubular shaft on which the ascasrs ring geary |4aof the second planetary gearing 8a and thefturbine jrotor rI3'of the second torque converter are secured, the sunl gear Il of which is keyed to the intermediate shaft 3 and the gear carrier 22 of which is keyed to the driven shaft 2. One-way anchors 2l and 28 may be provided for preventing reverse rotation of the one-way stator rotor Il and ring gear 2l. 1

The operation oi' this form is broadly similar to that of Pigs. 1, 2, and 7, in that the turbine of the ilrst converter drives the pump of the second converter and that each turbine ofthe two converters drives an element of a planetary gearing, one of which elements is held against reverse rotation by a one-way anchor.

The construction shown in Fig. 9 comprises a drive shaft I, a driven shaft 2, an intermediate shaft 3. a first hydraulic coupler 21, the pump rotor 23 of which is secured to the drive shaft I, a 'second hydraulic coupler 21a, the pump rotor of which is rotatable with the turbine of the ilrst coupler and with the intermediate shaft 3, a third hydraulic coupler 21h, the' pump rotor of which is rotatable with the turbine rotor 3Ia of the second coupler and with the tubular shaft 88, and 'a compound planetary gearing construction 10. The compound planetary gearing construction comprises a-sun gear 1| keyed to the intermediate shaft 3, a ring gear 12 keyed to the tubular shaft 88, planet gearing 13 meshing with the sun gear 1I and ring gear 12, a gear carrier 14 on which the planet gearing 13 is mounted, a sleeve 15 rotatable with the gear carrier 14, a ring gear 18 rotatable with the sleeve 15, planet gearing 11 meshing with the sun gear 18 and ring gear 18, a tubular drum or sleeve 19 rotatable with the sun gear 18 and with the turbine rotor 3Ib of the third coupler, and a gear earrier 88 on which the planet gearing 11 is mounted, keyed to the driven shaft 2. A one-way anchor 8l is provided' to prevent reverse rotation of the sun Igear 18, and a one-way clutch 82 is provided to prevent the drum for sleeve 18 from overrunning the tubular shaft 88 on' which the ring gear 121s mounted. II

In this form, assuming that thecar is'standing still and that the motor -is running at an effective speed, in the first stagel or condition of the transmission the pump rotor 29 of the rst cou.- pler will pickupin speed Yuntil theturbine rotor 3| of the first coupler begins to move. This will cause rotation of' the sun gear `1 I. Rotation of the sungear 1I willcause a slow rotation of the gear carrier 14 and consequently of the ring gear-18,'since the ring gear 12 is held against retwo portions of the lduplex gear to `the pitch i radius of the larger gear portion, multiplied` by verse rotation by the clutch 82 and anchor 8l.

'Ifhis will cause a still lower rotation of the driven shaft 2 as the sun gear 18 isheld against reverse rotation by the one-way anchor 8|'. As the speed of the intermediate' shaft 3 increases, .the vpump rotor 28a of thesecondcouplerwill become effective to causethe turbine 3Ia..:of the second coupler yto rotate and to carry with it rthe ring gear 12. This will increasey the speed of the gear carrier 14,sleeve 15 and ringv'gear 18, the sun gear 18 being still held against reverse rotation by the anchor 8|. This is the second stage or condition of the transmission. As the turbine 3Ia of the second coupler 21a increases in speed, the pump rotor 28h of the third turbine will become eilective to cause the turbine rotor 3Ib of the third coupler to begin to move, carrying with it the sun gear 18 of the planetary gearing. This is the third stage or condition of the transmission. I'he first stage may give a torquel multiplication of about 5:14 depending .upon the proportionsof the planetary gearing.. The second stage fina! give a maximum torque multiplication of'1.5l:1, again depending on the gearrproportions. The third stage will ygive no torque multiplication, but as the speed of the turbines increases it will give almost a 1:1 speed ratio.

The construction shown in rig. io comprisesa drive shaft I,` a driven shaft [intermediate shaft 3, a hydraulic coupler 21, a hydraulic torque converter 8 in series with the coupler, and aplane.- tary gearing 83 in series with the hydraulic transmission.` The hydraulic vcoupler vcomprises a pump rotor 28 'keyed tothe drive shaft I and a turbine rotor 3I keyed vto the intermediate shaft 3. The hydraulic torque converter comprises the pump rotor 8 rotatable with the turbine r`o' tor 3| of the coupler, a turbine rotor 'I2 keyed to a sleeve 84 surrounding the `intermediate shaft 3, and a stator-rotor I3 held against reverse rotation by the one-way anchor 25.

The planetary gearing 83 comprises a gear carrier 88l keyed to the intermediate shaft 3,`duplex planet gearing 88 carried by vthe gear carrienw'a ring gear 81 meshing wit'i'nthe larger gear portion of the duplex gearing 88 `andV keyed to the sleeve 84, and a ring'geai'y neshing with the smaller gear portion of thedilex 'gearing 88 and keyed to the driven shaft 2. One-way anchors'25 and 28 are provided for preventing reverse rotation of the stator-rotor and ringI gear 81, respectively.v The' duplex planet gearing "may be designed to give anydesiredfspeed reduction between the intermediate shaft 3 and the driven shaft 2 when the ring' gear 81 is stationary.- For example, .if' a torque increase'of 1:10 is desired, the pitch diameters of the two portions of the duplex planetl gear 88 is madesuch thatthe ratio of the difference in thepitch radii o'f the the ratio of the pitchfradius ofthe gear carrier' 88 to the pitchradius of the ring gea'r88, .equals one-tenth.

and the driveshaft I is rotating at an effective"- speed during the vfirst stage' of operation,l the pump rotor ofthe coupler will increase irl-speedA until the turbine rotorv of the coupler beginstov rotate, `carrying with'it the gear carriereof the: planetary.V As the ring gear is held against re-I verse rotation by the anchor, the driven shaft 2f will be driven at a speed of one-tenthA the-speed ofthe intermediate shaft 3. As the turbineIrotorof the coupler increases in speed, the pump-rotor of the hydraulic converterwill begin toA be ef;l fective to cause rotation ofy the turbine' rotor of the converter. This willf eause the ring gear to begin toV rotate so .that'thereafter there'is a divided powerv flowv from the'turbine ofthercouf lpler, o ne path being throughfthe4 hydraulic converter and ring gear to'thefduplex planet' gear-l ing and .the other-'path .being through :the 1in-'5 termediateshaft 3 andztothe gear` carrier-ofthe planetary gearing. Thisf. f will give a. Ymaximum i torque multiplication of approximately 5:1.

Further modifications will be apparent to those skilled in the art and it is desired, therefore, that the invention be limited only by the scope of the appended claims.

Having thus described my invention, what I claim and desire to secure by Letters Patent is:

1. A hydraulic planetary transmission comprising two hydraulic torque converters, each comprising a pump rotor. a turbine rotor and a reprising two hydraulic torque converters, each comprising a pump rotor, a turbine rotor and a reactance guide, the pump rotor of the second converter being positively driven from the turbine rotor of the rst converter, planetary gearing comprising a sun gear positively driven from one of said turbine rotors, a ring gear positively driven from the other turbine rotor, a gear carrier and planet gearing mounted on said gear carrier and meshing with said sun gear and ring gear, a driving member, a shaft I extending through said converters, clutch means for connecting and disconnecting said shaft with respect to said driving member, and clutch means for connecting and disconnecting said gear car rier with respect to said shaft.

3. A hydraulic planetary transmission comprising two hydraulic torque converters, each comprising a pump rotor, a turbine rotor and a re-4 actance guide, the pump rotor of the second converter being positively driven from the turbine rotor of the first converter, planetary gearing comprising a sungea'r positively driven from one of said turbine rotors, a ring gear positively driven from the other turbine rotor, a gear carrier and planet gearing mounted on said Sear carrier and meshing with said sun gear and ring gear, a driving member, a shaft extending through said converters, clutch means for connecting and disconnecting said shaft with respect to said driving member, and one-way clutch means for connecting and disconnecting said gear carrier with respect to said shaft.

4. A hydraulic planetary transmission comprising two hydraulic torque converters, each comprising a pump rotor. a turbine rotor and a reactance guide, the pump rotor of the second converter being positively driven from the turbine rotor of the iirst converter, and planetary gearing comprising a sun gear positively driven from one of said turbine'rotors, a ring gear positively driven from the other turbine rotor, a gear carrier and planet gearing mounted on said gear carrier and meshing with said sun gear and ring gear, one of said reactance guides comprising a stato-rotor and a one-way anchorage for preventing reverse rotation-of said stato-rotor.

Y 5. A hydraulic planetary transmission comprising two hydraulic torque converters, each comprising a pump rotor, a'. turbine rotor and a 1reactance guide, the pump rotor of the second converter being positively driven from the turbine assenza rotor of the first converter, and-planetary gearing comprising a sun gear positively driven from one of said turbine rotors. a ring gear positively drivenl from the other turbine rotor, a gear carrier and planet gearing mounted on said gear carrier and meshing with said sun gear and ring gear, each of said reactance guides comprising a, stato-rotor and one-way anchorage means for .preventing reverse rotation of both of said stato- 6. Ahydro-planetary transmission comprising a drive shaft, a driven shaft, -an intermediate one-piece unitary shaft, a first hydraulic torque transmission unit including a first pump rotor driven from said drive shaft and a first turbine rotor actuated by liquid from said first pump rotor andsecured to said unitary shaft, a second hydraulic torque transmission unit including a second pump rotor driven positively by said rst turbine rotor and secured to said unitary shaft, and a second turbine rotor actuated by liquid from said second pump rotor, a planetary gearing comprising three elements (1) a first gear, (2) a second gear, and (3) a gear carrier and planetary gearing carried thereby and meshing with said gears, said gear carrier being secured to said driven shaft, said rst gear being secured to said unitary shaft andpositively driven by said first turbine rotor, said second gear being positively driven by said second turbine rotor, and one-way anchorage means for holding said second gear against reverse rotation with respect to said second turbine rotor, said intermediate unitary shaft extending through and supporting said first turbine rotor, .said second pump rotor, said second turbine rotor, and said iirst gear.

`'1. A hydro-planetary transmission comprising a drive shaft, a. driven shaft, an intermediate one-piece unitary shaft, a irst hydraulic torque transmission unit including a first pump rotor driven from said drive shaft and-a first turbine rotor actuated by liquidV from said first pump' I rotor and secured to said unitary shaft, a second hydraulic torque transmission unit including a second pump rotor driven positively by said irst turbine rotor and secured to said unitary shaft, and a second turbine rotor actuated by liquid from said second pump rotor, a planetary gearing comprising three elements (1) a sun gear, (2) a ring gear, and (3) a gear carrier and pianetary gearing carried thereby and meshing with said gears, said gear carrier being secured to said driven shaft, said sun gear being secured to said unitary shaft and positively driven by said rst turbine rotorfsaid ring gear being positively driven by said second turbine rotor, and one-way anchorage means for holding said ring gear against reverse rotation with respect to said second turbine rotor, said intermediate unitary shaft extending through and supporting said first turbine rotor, said second pump rotor, said second turbine rotor, and said sun gear. v

WILLARD L. POLLARD. 

